Outside Influence is a mod for the original Portal; a new story set within the shared Half-Life/Portal universe, with new testing elements, environments and music. Contains additional features, such as fully voiced audio logs that tell the stories of those who worked at Aperture Science in its last days, a togglable hint system and a zoom scope a la Portal 2.

Yes! We've got a pretty big voice cast - Jim Sterling, Conrad Zimmerman (who is also acting as script editor), Jonathan Holmes, Cody Powell, Clint of LazyGameReviews, and a bunch more folks who I've followed work of in the past. I've got a few more to ask yet, and a couple that have yet to reply (though I was perhaps a tad optimistic in asking Marc Leblanc and Warren Spector, but I thought I'd give it a go )

Oh, and if you're wondering why there's such a large cast, the game features audio-logs. Yes, I played System Shock in the past year, can you tell?

Honestly? I wanted to see how far it could get without leveraging the name-power. We're very nearly in the top 100 even though it's not been featured on a single major games site - TWP is the only site to have done so, as far as I can tell. Word of mouth has gotten us pretty damn far.

I plan on sticking up an announcement about the voice cast later this week, however.

Thanks! I've often thought about switching to Portal 2, but I want to force myself to avoid some of the pitfalls of Portal 2's design (big empty cavernous areas with boxes in, relying on dynamic lighting etc.). Simply using the older engine is the easiest way of doing that, really.